1968157440 has 360 divisors, whose sum is σ = 7229775168. Its totient is φ = 510935040.

The previous prime is 1968157409. The next prime is 1968157441. The reversal of 1968157440 is 447518691.

1968157440 is a `hidden beast` number, since 19 + 68 + 1 + 574 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1968157441) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4250649 + ... + 4251111.

Almost surely, 2^1968157440 is an apocalyptic number.

1968157440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1968157440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3614887584).

1968157440 is an abundant number, since it is smaller than the sum of its proper divisors (5261617728).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1968157440 is an equidigital number, since it uses as much as digits as its factorization.

1968157440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537 (or 514 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The square root of 1968157440 is about 44363.9204759904. The cubic root of 1968157440 is about 1253.1987280622.

The spelling of 1968157440 in words is "one billion, nine hundred sixty-eight million, one hundred fifty-seven thousand, four hundred forty".